Stream data broadcasting for mobile reception terminals is being focused on as a technique to enable easy enjoyment of stream data such as audio and video at any place and time.
Stream data that is broadcast in stream data broadcasts for mobile reception terminals include IDR pictures that can be played independently without referencing images before and after. When receiving and recording such stream data on a mobile reception terminal, for each IDR picture, the mobile reception terminal measures a stream time (hereinafter called an offset time) from the beginning of the stream data until playback of the IDR picture, generates index information, and records the index information along with the stream data. The index information correlates the measured offset time, an index number (hereinafter, called a TPI: Transport Packet Index) that indicates where in the stream data a TS (Transport Stream) packet corresponding to the head of a PES (Packetized Elementary Stream) including the IDR picture is located, a PTS (Presentation Time Stamp) of the IDR picture, and a data amount that is to be read in order to acquire the recorded IDR picture. Recording such index information along with the stream data enables designation of and playback starting from an IDR picture at an arbitrary time in the stream when the recorded stream data is being viewed. Generation and use of such meta-information enables so-called seeking to a user-specified arbitrary time in the stream data (hereinafter called a seek time).
In digital delivery of stream data, representative of which is digital broadcasting and Internet delivery, transmission signals include noise due to the influence of, for example, reflections off of buildings, and reflections in a network cable during signal transmission, which causes transmission errors. For this reason, in conventional digital delivery, transmission errors are handled by the employment of coding methods that enable error correction on the reception side, such as BdH (Bose, Chaudhuri, Hocquenghem) code and RS (Read Solomon) code.    Patent document 1: Japanese Patent Application Publication No. 2001-309262